Researchers find shade from stand density can cost farmers about 10% of potential crop yield 30 January 2017 A team from the University of Illinois has found that compared to top leaves, the shaded lower level leaves of C4 crops planted in dense stands such as corn and Miscanthus underperform, costing farmers about 10% of potential yield. These findings, published in an open-access paper in the Journal of Experimental Botany , could help scientists further boost the yields of corn and Miscanthus, as well as other C4 crops that have evolved to photosynthesize more efficiently than C3 plants such as wheat and rice. In modern intensive systems, crops form dense canopies where both sun and shade leaves contribute to photosynthetic carbon assimilation and productivity. Shaded leaves are estimated to contribute about 50% of total canopy carbon gain and therefore the efficiency w...